L'Osservatore Romano Vatican-Pool/Getty Images(VATICAN CITY) -- With his resignation set for Thursday, Pope Benedict XVI published a declaration on Monday to allow the College of Cardinals to begin choosing his successor almost immediately after he steps down.

The conclave could start in early March, sidestepping an edict by John Paul II that the election of a new pope should not take place until 15 days after the pontiff has died.

However, given the unusual circumstances leading to this conclave -- Benedict is the first pope to abdicate in nearly 600 years -- it was decided that the cardinals shouldn’t have to wait longer than necessary to find the next leader of the Roman Catholic Church.

Cardinals are already arriving at the Vatican in Rome. All told, 117 cardinals under the age of 80 will take part in the conclave.

Benedict, 85, announced two weeks ago he was resigning due to his age and health concerns.